FIG. 1.
Growth characteristics of strains carrying single and double mutant combinations of ssy5, ssy1, and ptr3 null alleles. Strains PLY126 (wild type [WT]), HKY20 (ssy1Δ13), HKY31 (ptr3Δ15), HKY77 (ssy5Δ2), HKY33 (ssy1Δ13 ptr3Δ15), HKY84 (ssy5Δ2 ssy1Δ13), and HKY85 (ssy5Δ2 ptr3Δ15) were streaked onto the following media: SPD (plus uracil and lysine) (A), SPD (plus uracil and lysine) containing 30 mM l-histidine (B), SPD (plus uracil and lysine) containing 30 mM l-methionine (C), SD (plus uracil and lysine) (D), and SD (plus uracil and lysine) containing 100 μg of l-azetidine-2-carboxylate ml−1 (E). Plates were incubated for 3 days at room temperature and photographed.